1 /* 2 * ASPEED Real Time Clock 3 * Joel Stanley <joel@jms.id.au> 4 * 5 * Copyright 2019 IBM Corp 6 * SPDX-License-Identifier: GPL-2.0-or-later 7 */ 8 9 #include "qemu/osdep.h" 10 #include "hw/rtc/aspeed_rtc.h" 11 #include "migration/vmstate.h" 12 #include "qemu/log.h" 13 #include "qemu/timer.h" 14 #include "sysemu/rtc.h" 15 16 #include "trace.h" 17 18 #define COUNTER1 (0x00 / 4) 19 #define COUNTER2 (0x04 / 4) 20 #define ALARM (0x08 / 4) 21 #define CONTROL (0x10 / 4) 22 #define ALARM_STATUS (0x14 / 4) 23 24 #define RTC_UNLOCKED BIT(1) 25 #define RTC_ENABLED BIT(0) 26 27 static void aspeed_rtc_calc_offset(AspeedRtcState *rtc) 28 { 29 struct tm tm; 30 uint32_t year, cent; 31 uint32_t reg1 = rtc->reg[COUNTER1]; 32 uint32_t reg2 = rtc->reg[COUNTER2]; 33 34 tm.tm_mday = (reg1 >> 24) & 0x1f; 35 tm.tm_hour = (reg1 >> 16) & 0x1f; 36 tm.tm_min = (reg1 >> 8) & 0x3f; 37 tm.tm_sec = (reg1 >> 0) & 0x3f; 38 39 cent = (reg2 >> 16) & 0x1f; 40 year = (reg2 >> 8) & 0x7f; 41 tm.tm_mon = ((reg2 >> 0) & 0x0f) - 1; 42 tm.tm_year = year + (cent * 100) - 1900; 43 44 rtc->offset = qemu_timedate_diff(&tm); 45 } 46 47 static uint32_t aspeed_rtc_get_counter(AspeedRtcState *rtc, int r) 48 { 49 uint32_t year, cent; 50 struct tm now; 51 52 qemu_get_timedate(&now, rtc->offset); 53 54 switch (r) { 55 case COUNTER1: 56 return (now.tm_mday << 24) | (now.tm_hour << 16) | 57 (now.tm_min << 8) | now.tm_sec; 58 case COUNTER2: 59 cent = (now.tm_year + 1900) / 100; 60 year = now.tm_year % 100; 61 return ((cent & 0x1f) << 16) | ((year & 0x7f) << 8) | 62 ((now.tm_mon + 1) & 0xf); 63 default: 64 g_assert_not_reached(); 65 } 66 } 67 68 static uint64_t aspeed_rtc_read(void *opaque, hwaddr addr, 69 unsigned size) 70 { 71 AspeedRtcState *rtc = opaque; 72 uint64_t val; 73 uint32_t r = addr >> 2; 74 75 switch (r) { 76 case COUNTER1: 77 case COUNTER2: 78 if (rtc->reg[CONTROL] & RTC_ENABLED) { 79 rtc->reg[r] = aspeed_rtc_get_counter(rtc, r); 80 } 81 /* fall through */ 82 case CONTROL: 83 val = rtc->reg[r]; 84 break; 85 case ALARM: 86 case ALARM_STATUS: 87 default: 88 qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr); 89 return 0; 90 } 91 92 trace_aspeed_rtc_read(addr, val); 93 94 return val; 95 } 96 97 static void aspeed_rtc_write(void *opaque, hwaddr addr, 98 uint64_t val, unsigned size) 99 { 100 AspeedRtcState *rtc = opaque; 101 uint32_t r = addr >> 2; 102 103 switch (r) { 104 case COUNTER1: 105 case COUNTER2: 106 if (!(rtc->reg[CONTROL] & RTC_UNLOCKED)) { 107 break; 108 } 109 /* fall through */ 110 case CONTROL: 111 rtc->reg[r] = val; 112 aspeed_rtc_calc_offset(rtc); 113 break; 114 case ALARM: 115 case ALARM_STATUS: 116 default: 117 qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr); 118 break; 119 } 120 trace_aspeed_rtc_write(addr, val); 121 } 122 123 static void aspeed_rtc_reset(DeviceState *d) 124 { 125 AspeedRtcState *rtc = ASPEED_RTC(d); 126 127 rtc->offset = 0; 128 memset(rtc->reg, 0, sizeof(rtc->reg)); 129 } 130 131 static const MemoryRegionOps aspeed_rtc_ops = { 132 .read = aspeed_rtc_read, 133 .write = aspeed_rtc_write, 134 .endianness = DEVICE_NATIVE_ENDIAN, 135 }; 136 137 static const VMStateDescription vmstate_aspeed_rtc = { 138 .name = TYPE_ASPEED_RTC, 139 .version_id = 2, 140 .fields = (const VMStateField[]) { 141 VMSTATE_UINT32_ARRAY(reg, AspeedRtcState, 0x18), 142 VMSTATE_INT64(offset, AspeedRtcState), 143 VMSTATE_END_OF_LIST() 144 } 145 }; 146 147 static void aspeed_rtc_realize(DeviceState *dev, Error **errp) 148 { 149 SysBusDevice *sbd = SYS_BUS_DEVICE(dev); 150 AspeedRtcState *s = ASPEED_RTC(dev); 151 152 sysbus_init_irq(sbd, &s->irq); 153 154 memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_rtc_ops, s, 155 "aspeed-rtc", 0x18ULL); 156 sysbus_init_mmio(sbd, &s->iomem); 157 } 158 159 static void aspeed_rtc_class_init(ObjectClass *klass, void *data) 160 { 161 DeviceClass *dc = DEVICE_CLASS(klass); 162 163 dc->realize = aspeed_rtc_realize; 164 dc->vmsd = &vmstate_aspeed_rtc; 165 dc->reset = aspeed_rtc_reset; 166 } 167 168 static const TypeInfo aspeed_rtc_info = { 169 .name = TYPE_ASPEED_RTC, 170 .parent = TYPE_SYS_BUS_DEVICE, 171 .instance_size = sizeof(AspeedRtcState), 172 .class_init = aspeed_rtc_class_init, 173 }; 174 175 static void aspeed_rtc_register_types(void) 176 { 177 type_register_static(&aspeed_rtc_info); 178 } 179 180 type_init(aspeed_rtc_register_types) 181